This invention relates to absorbent pads which adhere to surfaces to be protected from fluid and, more particularly, to a method of manufacturing such absorbent pads through a continuous production technique comprising multiple steps.
Absorbent pads find many common uses, such as in the management of bodily fluids. The utility of such products often derives not only from their absorbent properties but also their ability to prevent the further contact of absorbed fluids with certain surfaces, such as clothing or skin. Such containment is often achieved through the incorporation of a fluid-impermeable barrier layer on one or more surfaces of the absorbent pad. Diapers, bandages, and feminine sanitary napkins provide examples of absorbent pads comprising a fluid-impermeable barrier layer.
In addition to containing and isolating fluids, it is often also desirable for absorbent pads be secured to a particular surface or in a certain position. For example, it is known in the art to secure a sanitary napkin by affixing its barrier layer to a woman's undergarment, typically through the use of adhesives.
Unfortunately, however, the processes traditionally employed in the manufacture of absorbent pads--securable or otherwise--have often involved a series of separate and preliminary raw material processing procedures. Upon completion of such processing, the resultant components must be inventoried and then assembled into a single, integrated product. Such assembly traditionally involves securing various, fully formed components to a pulp core with adhesive. The implementation of multiple, separately processed adhesive-bound raw material components thus typically adds considerable expense and delay to the production of absorbent pads and increases the likelihood of bunching and other forms of pad instability in actual use.
Accordingly, considerable effort has been expended to consolidate the various procedures required in the manufacture of absorbent pads. For example, U.S. Pat. Nos. 4,530,353, 4,545,372, 4,549,653, and 4,607,633, all in the name of Lauritzen, disclose continuous and considerably streamlined production techniques for the manufacture of adhesive bandages and packages therefor. The objects of these patents, however, comprise an absorbent pad area having adjacent adhesive areas and are designed to attach to fluid-bearing surfaces; an item such as a sanitary napkin commonly bears adhesive, if at all, on the surface opposite its absorbent cover and is designed to attach to a surface for which protection from fluid is sought.
It is accordingly an object of the present invention to provide an improved absorbent pad. It is another object of the present invention to provide a low cost absorbent pad through the use of low cost manufacturing techniques. It is a further object of the present invention to provide an absorbent pad having a fluid-impermeable barrier layer. It is still another object of this invention to provide an absorbent pad having both a barrier layer and a means for attachment to a surface to be protected from fluid. It is yet another object of this invention to manufacture such an absorbent pad through a continuous production technique in which all necessary raw material components are incorporated in a stepwise fashion and are bound together in a unitary design not employing adhesives.